The application, made by Scottish and Southern Energy (SSE) unit SSE Generation, is to build a pumped storage plant to add a further 100GWh of electricty to annual generation – almost doubling output.

Existing capacity at the site, near Loch Lomond, is 152MW.

The budget for the project is more than £30M (US$50M).

Separately, SSE declined to comment on findings, repair work or operational status of the recently opened 100MW Glendoe plant following a rockfall in the headrace tunnel, leading from the reservoir. The facility’s equipment had suffered no damage, it said when the problem was reported